Flexible line trimmer head

Abstract

A flexible line trimmer head has a housing with first and second parts and a spool for a supply of line. The first and second housing parts are configured to be moved from a spaced relationship towards each other along an operating axis whereupon cooperating connectors engage to block movement of the first and second housing parts away from each other along the axis. The cooperating connectors are provided in pairs at at least three different locations each spaced radially from the operating axis and in a circumferential direction from the other locations.

The invention claimed is: 
     
       1. A flexible line trimmer head comprising:
 a housing comprising a first part and a second part each having a central axis, 
 the housing having an operating axis; 
 a spool around which a supply of flexible line can be wrapped and having an axis, 
 the first and second housing parts configured to be moved axially relative to each other between: a) a first state wherein the first and second housing parts are separated from each other; and b) a second state wherein the first and second housing parts are operatively connected, 
 the housing and spool configured so that the spool: a) is maintained in an operative position on the housing between portions of the first and second housing parts with the first and second housing parts in the second state; and b) can be separated from the housing with the first and second housing parts in the first state; and 
 the flexible trimmer head further comprising a connecting assembly configured to be engaged by a drive that is operated to cause the first and second housing parts in the second state to be driven around the operating axis, 
 the first and second housing parts having cooperating connector pairs at at least three locations, 
 the cooperating connector pairs at each location configured to block movement of the first and second housing parts axially away from each other with the first and second housing parts in the second state, 
 each of the locations spaced: a) radially from the operating axis; and b) in a circumferential direction from the other locations, 
 wherein a first of the cooperating connector pairs comprises a first repositionable arm with a surface/edge facing a first axial direction on one of the first and second housing parts and a surface/edge on the other of the first and second housing parts facing oppositely to the first axial direction, 
 wherein the housing is configured so that with the first and second housing parts in the first state, relative movement of the first and second housing parts axially towards and against each other causes at least a part of the first repositionable arm to be deflected radially in one direction by the other of the first and second housing parts to allow the surfaces/edges on the first and second housing parts to move up to and past each other whereupon with the first and second housing parts realizing the second state the at least part of the first repositionable arm moves radially oppositely to the one direction so that the surfaces/edges are in confronting relationship so as to block movement of the first and second housing parts axially away from each other at the location of the first cooperating connector pairs, 
 wherein the other of the first and second housing parts has a peripheral wall extending around the operating axis and the surface/edge on the other of the first and second housing parts is on the peripheral wall, 
 wherein there is a first tab on one of the first and second housing parts and a first notch on the other of the first and second housing parts, the first tab and first notch configured to cooperate with each other at a location spaced from the cooperating connector pairs to key the first and second housing parts against relative movement around the operating axis, the first tab movable into and out of the first notch as the first and second housing parts are changed back and forth between the first and second states without requiring any direct manipulation of the first tab by a user, 
 wherein the other of the first and second housing parts has an annular wall with an exposed outside surface facing radially outwardly and the first notch extends through the exposed outside surface. 
 
     
     
       2. The flexible line trimmer head according to  claim 1  wherein the first and second housing parts have cooperating connector pairs at at least four locations, each of the locations spaced: a) radially from the operating axis; and b) in a circumferential direction from the other locations. 
     
     
       3. The flexible line trimmer head according to  claim 2  wherein first and second of the cooperating connector pairs are at diametrically opposite first and second of the locations and are substantially symmetrical on opposite sides of a first reference plane including the operating axis and third and fourth of the cooperating connector pairs are at diametrically opposite third and fourth of the locations and are substantially symmetrical on opposite sides of a second reference plane including the operating axis. 
     
     
       4. The flexible line trimmer head according to  claim 2  wherein the housing further defines diametrically opposite openings each of which is configured to allow passage of a length of flexible line from the spool radially to outside of the housing. 
     
     
       5. The flexible line trimmer head according to  claim 2  wherein the housing further defines diametrically opposite openings at fifth and sixth locations each of which is configured to allow passage of a length of flexible line from the spool radially to outside of the housing and the first, second, third, fourth, fifth, and sixth locations are spaced substantially uniformly from each other in a circumferential direction. 
     
     
       6. The flexible line trimmer head according to  claim 5  wherein there are first and second tabs and first and second notches on the first and second housing parts, the first tab and first notch configured to cooperate with each other to key the first and second housing parts against relative movement around the operating axis at one location and the second tab and second notch are configured to cooperate with each other to key the first and second housing parts against relative movement around the operating axis at a location spaced circumferentially from the one location, the one location and the location spaced circumferentially from the one location each spaced from where the cooperating connector pairs are located. 
     
     
       7. The flexible line trimmer head according to  claim 6  wherein the first tab has a different shape than the second tab. 
     
     
       8. The flexible line trimmer head according to  claim 6  wherein the first tab has a different circumferential dimension than the second tab. 
     
     
       9. The flexible line trimmer head according to  claim 1  wherein each of the cooperating connector pairs has the same construction as the first cooperating connector pair. 
     
     
       10. The flexible line trimmer head according to  claim 1  wherein the first repositionable arm is a cantilevered arm that bends to allow the surface/edge on the first repositionable arm to move in radial opposite directions. 
     
     
       11. The flexible line trimmer head according to  claim 10  wherein the one of the first and second housing parts comprises a molded body and the first repositionable arm is molded as one part of the body. 
     
     
       12. The flexible line trimmer head according to  claim 1  wherein the spool has a core and further in combination with a supply of flexible line wrapped around the spool core. 
     
     
       13. The flexible line trimmer head according to  claim 1  wherein the housing has a top and a bottom spaced axially from the top and the flexible line trimmer head further comprises a cap at the top of the housing that is configured to be turned guidingly around the operating axis to thereby turn the spool relative to the housing parts around the operating axis. 
     
     
       14. The flexible line trimmer head according to  claim 1  wherein the flexible line trimmer head is configured so that an engaged drive causes the spool to turn the first and second housing parts around the operating axis. 
     
     
       15. The flexible line trimmer head according to  claim 1  wherein the first and second housing parts make up a housing unit and there are components cooperating between the spool and housing unit that are configured to allow incremental turning of the housing unit relative to the spool upon the housing unit and spool being momentarily axially moved relative to each other with the housing unit driven around the operating axis. 
     
     
       16. The flexible line trimmer head according to  claim 1  wherein the first and second housing parts make up a housing unit and a spring biasing structure urges the housing unit in one axial direction relative to the spool. 
     
     
       17. A housing unit comprising the first and second housing parts in  claim 1 . 
     
     
       18. The housing unit according to  claim 17  wherein the first and second housing parts have cooperating connector pairs at at least four locations, each of the locations spaced: a) radially from the operating axis; and b) in a circumferential direction from the other locations. 
     
     
       19. The housing unit according to  claim 18  wherein first and second of the cooperating connector pairs are at diametrically opposite first and second of the locations and are substantially symmetrical on opposite sides of a first reference plane including the operating axis and third and fourth of the cooperating connector pairs are at diametrically opposite third and fourth of the locations and are substantially symmetrical on opposite sides of a second reference plane including the operating axis, wherein the first and second reference planes are non-orthogonal to each other. 
     
     
       20. The flexible line trimmer head according to  claim 1  wherein an edge portion bounding the first notch and an edge portion on the first tab cooperate over a substantial axial extent to avoid skewing of a relationship between the central axes of the first and second housing parts. 
     
     
       21. The flexible line trimmer head according to  claim 1  wherein there is a second tab on one of the first and second housing parts and a second notch on the other of the first and second housing parts that cooperate with each other as the first tab and first notch cooperate as the first and second housing parts are changed between the first and second states and the first tab has a different shape than the second tab. 
     
     
       22. A flexible line trimmer head comprising:
 a housing comprising a first part and a second part, 
 the housing having an operating axis; 
 a spool around which a supply of flexible line can be wrapped, 
 the first and second housing parts configured to be moved axially relative to each other between: a) a first state wherein the first and second housing parts are separated from each other; and b) a second state wherein the first and second housing parts are operatively connected, 
 the housing and spool configured so that the spool: a) is maintained in an operative position on the housing with the first and second housing parts in the second state; and b) can be separated from the housing with the first and second housing parts in the first state; and 
 the flexible trimmer head further comprising a connecting assembly configured to be engaged by a drive that is operated to cause the first and second housing parts in the second state to be driven around the operating axis, 
 the first and second housing parts having cooperating connector pairs at at least three locations, 
 the cooperating connector pairs at each location configured to block movement of the first and second housing parts axially away from each other with the first and second housing parts in the second state, 
 each of the locations spaced: a) radially from the operating axis; and b) in a circumferential direction from the other locations, 
 wherein there is a first tab on one of the first and second housing parts and a first notch on the other of the first and second housing parts, the first tab and first notch spaced from the cooperating connector pairs and configured to cooperate with each other to key the first and second housing parts against relative movement around the operating axis, 
 wherein the first tab is movable into and out of the first notch as the first and second housing parts are changed back and forth between the first and second states without requiring any direct manipulation of the first tab by a user, 
 wherein the other of the first and second housing parts has an annular outer wall with an axial extent and the first notch extends through the annular outer wall, and the first notch and the first tab extend over a substantial portion of the axial extent of the annular outer wall so as to stabilize the joined housing parts. 
 
     
     
       23. A housing unit comprising the first and second housing parts in  claim 22 .